1. Field of the Invention
This invention relates to a microscope and, more particularly, it relates to a microscope specifically designed to hermetically seal and protect the objective lens and the specimen when the microscope is not in use but in storage.
2. Prior Art
In conventional microscopes, a plurality of objective lenses having different respective magnifying factors are normally fitted to a rotary member normally referred to as an objective turret or revolver so that a desired magnifying factor may be selected by turning the objective turret, while the stage of the microscope, which is a stationary flat member, is provided with a sliding holder for holding a specimen prepared and carried on a small glass plate for microscope observation.
In conventional microscopes of the above described type comprising a plurality of objective lenses, one of which is selected and placed on the optical axis of the optical system of the microscope, the stage of the microscope, which is a stationary flat member, is provided with a sliding holder for holding a specimen or a petri dish containing a liquid specimen or liquid by turn containing a specimen.
Conventional microscopes of the above described type are inevitably bulky because a plurality of objective lenses are fitted to an objective turret and comprise a large number of parts. Additionally, the operation of turning the objective turret is not an easy one for children who can inadvertently move the microscope that has been placed in position and/or the specimen that has been secured to the stage.
Still additionally, it is rather difficult to optically regulate the microscope if it comprises a plurality of objective lenses fitted to an objective turret.
Meanwhile, when the microscope is not in use, the objective lenses and the stage are exposed to the atmosphere so that fine pieces of dust can easily be collected there.
Additionally, they can be adversely affected by moisture in the atmosphere. On the other hand, a large container will be required for storing the objective lenses and the stage in a hermetically sealed state and hence the use of such a large container is not feasible.
The stage is designed simply for receiving a specimen on a flat area thereof. A specimen containing plankton is placed in a petri dish, which is by turn placed on the stage for microscopic observation. However, petri dishes are rather bulky and apt to be broken so that it is difficult to safely store them.
With the focussing mechanism of known microscopes, the specimen is brought into focus by regulating the distance between the objective lens system and the stage. For example, the object lens system is rigidly secured to the microscope main body while the stage is held by the microscope main body and made movable along the main optical axis of the optical system. However, objective lenses having different magnifying factors require different moving distances between the optical system and the specimen on the stage. Therefore, when one of the objective lenses is selected and manipulated to bring the specimen into focus, some or the remaining objective lenses may collide with the specimen or the stage. Or, there may be cases where the specimen on the stage would not come into focus at all.
In view of the above identified problems of known microscopes, it is therefore an object of the present invention to provide a compact microscope that comprises a reduced number of parts and does not use an objective turret, while it is adapted to select a desired magnifying factor with ease and free from the risk of making difficult the effort of bringing the specimen into focus.
Another object of the present invention is to provide a microscope that can be easily regulated for focussing at the time of assembly and also at the time of using it for microscope observation.
Still another object of the present invention is to provide a microscope whose objective lenses and stage are protected against exposure to the atmosphere when it is not in use and also prevented from collecting fine pieces of dust and being adversely affected by moisture in the atmosphere.
Still another object of the present invention is to provide a microscope with which a specimen of liquid that contains plankton can be placed on the stage for microscopic observation without using a petri dish.
A further object of the present invention is to provide a microscope with which objective lenses of different magnifying factors can be efficiently and conveniently used without the risk of colliding with the stage and that of being unable to bring the specimen into focus to a certain extent.